Intravision/reactos
1
0
Fork 0
mirror of https://github.com/reactos/reactos.git synced 2025-04-05 13:11:22 +00:00
Code Issues Projects Releases Packages Wiki Activity

[NTOS:PNP] Avoid recursion in IopTraverseDeviceTree(Node). CORE-17215

Browse source
This commit is contained in:
Thomas Faber 2020-08-17 04:05:53 +02:00
parent 5cb9f8765b
commit ae1d272add
No known key found for this signature in database
GPG key ID: 076E7C3D44720826
1 changed files with 46 additions and 41 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

87
ntoskrnl/io/pnpmgr/devnode.c
View file

@ -321,56 +321,36 @@ IopFreeDeviceNode(
static
NTSTATUS
IopTraverseDeviceTreeNode(
IopFindNextDeviceNodeForTraversal(
_In_ PDEVICETREE_TRAVERSE_CONTEXT Context)
{
PDEVICE_NODE ParentDeviceNode;
PDEVICE_NODE ChildDeviceNode;
PDEVICE_NODE NextDeviceNode;
NTSTATUS Status;
/* Copy context data so we don't overwrite it in subsequent calls to this function */
ParentDeviceNode = Context->DeviceNode;
/* HACK: Keep a reference to the PDO so we can keep traversing the tree
* if the device is deleted. In a perfect world, children would have to be
* deleted before their parents, and we'd restart the traversal after
* deleting a device node. */
ObReferenceObject(ParentDeviceNode->PhysicalDeviceObject);
/* Call the action routine */
Status = (Context->Action)(ParentDeviceNode, Context->Context);
if (!NT_SUCCESS(Status))
/* If we have a child, simply go down the tree */
if (Context->DeviceNode->Child != NULL)
{
ObDereferenceObject(ParentDeviceNode->PhysicalDeviceObject);
return Status;
ASSERT(Context->DeviceNode->Child->Parent == Context->DeviceNode);
Context->DeviceNode = Context->DeviceNode->Child;
return STATUS_SUCCESS;
}
/* Traversal of all children nodes */
for (ChildDeviceNode = ParentDeviceNode->Child;
ChildDeviceNode != NULL;
ChildDeviceNode = NextDeviceNode)
while (Context->DeviceNode != Context->FirstDeviceNode)
{
/* HACK: We need this reference to ensure we can get Sibling below. */
ObReferenceObject(ChildDeviceNode->PhysicalDeviceObject);
/* Pass the current device node to the action routine */
Context->DeviceNode = ChildDeviceNode;
Status = IopTraverseDeviceTreeNode(Context);
if (!NT_SUCCESS(Status))
/* All children processed -- go sideways */
if (Context->DeviceNode->Sibling != NULL)
{
ObDereferenceObject(ChildDeviceNode->PhysicalDeviceObject);
ObDereferenceObject(ParentDeviceNode->PhysicalDeviceObject);
return Status;
ASSERT(Context->DeviceNode->Sibling->Parent == Context->DeviceNode->Parent);
Context->DeviceNode = Context->DeviceNode->Sibling;
return STATUS_SUCCESS;
}
NextDeviceNode = ChildDeviceNode->Sibling;
ObDereferenceObject(ChildDeviceNode->PhysicalDeviceObject);
/* We're the last sibling -- go back up */
ASSERT(Context->DeviceNode->Parent->LastChild == Context->DeviceNode);
Context->DeviceNode = Context->DeviceNode->Parent;
/* We already visited the parent and all its children, so keep looking */
}
ObDereferenceObject(ParentDeviceNode->PhysicalDeviceObject);
return Status;
/* Done with all children of the start node -- stop enumeration */
return STATUS_UNSUCCESSFUL;
}
NTSTATUS
@ -378,6 +358,7 @@ IopTraverseDeviceTree(
_In_ PDEVICETREE_TRAVERSE_CONTEXT Context)
{
NTSTATUS Status;
PDEVICE_NODE DeviceNode;
DPRINT("Context 0x%p\n", Context);
@ -387,8 +368,32 @@ IopTraverseDeviceTree(
/* Start from the specified device node */
Context->DeviceNode = Context->FirstDeviceNode;
/* Recursively traverse the device tree */
Status = IopTraverseDeviceTreeNode(Context);
/* Traverse the device tree */
do
{
DeviceNode = Context->DeviceNode;
/* HACK: Keep a reference to the PDO so we can keep traversing the tree
* if the device is deleted. In a perfect world, children would have to be
* deleted before their parents, and we'd restart the traversal after
* deleting a device node. */
ObReferenceObject(DeviceNode->PhysicalDeviceObject);
/* Call the action routine */
Status = (Context->Action)(DeviceNode, Context->Context);
if (NT_SUCCESS(Status))
{
/* Find next device node */
ASSERT(Context->DeviceNode == DeviceNode);
Status = IopFindNextDeviceNodeForTraversal(Context);
}
/* We need to either abort or make progress */
ASSERT(!NT_SUCCESS(Status) || Context->DeviceNode != DeviceNode);
ObDereferenceObject(DeviceNode->PhysicalDeviceObject);
} while (NT_SUCCESS(Status));
if (Status == STATUS_UNSUCCESSFUL)
{
/* The action routine just wanted to terminate the traversal with status